January 16, 1914] 



SCIENCE 



91 



the Diflferentiation of Lactose-fermenting Ba- 

 cilli with Special Eeference to those of Intes- 

 tinal Origin. Journal of Hygiene, IX., 86. 



Morse, M. E. 1912. A Study of the Diphtheria 

 Group of Organisms by the Biometrical Method. 

 Journal of Infectious Diseases, XI., 253. 



Owen, W. L. 1911. The Bacterial Deterioration 

 of Sugars. Bulletin No. 125, Agricultural Ex- 

 periment Station, Louisiana State University 

 and A. C. M. College. 



Penpold, W. J. 1912. On the Specificity of Bac- 

 terial Mutation with a Eesume of the Results of 

 an Examination of Bacteria found in Feces and 

 Urine which undergo Mutation when Grown on 

 Lactose Media. Journal of Hygiene, XII., 195. 



Eettgek, L. F., and Sherrick, J. L. 1911. 

 Studies on Bacterial Variation. Journal of 

 Medical Research, XXIV., 265. 



Rogers, L. A., and Davis, B. J. 1912. Methods 

 of Classifying the Lactic-acid Bacteria. Bul- 

 letin 154, V. S. Bureau of Animal Industry. 



Stowell, E. C, Hilliard, C. M., and Schlesinger, 

 M. J. 1913. A Statistical Study of the Strepto- 

 cocci from Milk and from the Human Throat. 

 Journal of Infectious Diseases, XII., 144. 



White, B., and Avery, O. T. 1909. Observations 

 on Certain Lactic-acid Bacteria of the So-called 

 Bulgaricus Type. Centralblatt fiir Bakterio- 

 logic, Abth. II., XXV., 161. 



WiNSLOw, C.-E. A. 1912. The Classification of 

 the Streptococci by their Action upon Carbohy- 

 drates and Related Organic Media. Journal of 

 Infectious Diseases, X., 285. 



WXNSLOW, C.-E. A., AND ROGERS, A. F. 1906. A 

 Statistical Study of Generic Characters in the 

 Coccaceffi. Journal of Infectious Diseases, III., 

 485. 



WiNSLOW, C.-E. A., AND Walker, L. T. 1909. A 

 Case of Non-inheritance of Fluctuating Varia- 

 tions Among Bacteria. Journal of Infectious 

 Diseases, VI., 90. 



WiNSLovf, C.-E. A., and Winslow, Anne Rogers. 

 1908. Systematic Relationships of the Coecaceffl ; 

 with a Discussion of the Principles of Bacterial 

 Classification. New York. 



Wolf, F. 1909. Ueber Modificationen und Ex- 

 perimentell Ausgeloste Mutationen von Bacillus 

 Prodigiosus und Anderen Schizophyten. Zeit- 

 schrift fiir InduJctive Abstammungs- und Verer- 

 lungslehre, II., 90. 



ACADEMIC STUDENT ELECTIONS 

 In Science, October 24, 1913, are some in- 

 teresting tables exhibiting the results of much 



patient work by Dr. Frederick C. Ferry, dean 

 and professor of mathematics in Williams 

 College. His tables give the registration of 

 students taking various subjects of study in 

 eighteen American colleges and universities. 

 These subjects are commonly divided into 

 three groups, roughly determined by the na- 

 ture of the topics included. Thus, group I. 

 may be called the " language group " ; group 

 II., the " humanities group " ; and group III., 

 the " science group." The distribution of 

 work in each of these groups in any given col- 

 lege affords some indication of the popularity 

 of the group. To express this distribution it 

 is necessary to give, as Dean Ferry has done, 

 for each subject the number of " student hours 

 of instruction." In view of the great varia- 

 tion in total attendance at different colleges- 

 Dean Ferry has reduced his figures to percen- 

 tages, on a semester basis, limiting them to 

 undergraduates in the academic college. 



On examining Dean Ferry's tables the pres- 

 ent vsTiter perceived the possibility of making 

 the comparisons somewhat more pointed, and 

 of securing a fair representation of popularity 

 not only for groups but for separate subjects 

 of study. A " student-hour of instruction " 

 may be interpreted to mean one hour per week 

 in the classroom, taken by one student through- 

 out one semester. The actual work done in- 

 cludes an estimated pair of hours spent in 

 study in preparation for the work of the class- 

 room. This estimate is often not realized, the 

 student taking his chances of escaping a test, 

 especially if the class is rather large. Two or 

 three hours in the laboratory are hence fairly 

 counted as the equivalent of one hour in the 

 classroom. Let h denote the value in student- 

 hours for a given course; for example, if the 

 student has 3 meetings per week in the class- 

 room and 2 afternoons per week in the labora- 

 tory, then h = 5. Let n denote the number of 

 students taking this course during a given 

 semester; then nh denotes the work done in 

 this course. 



Now, let 2(nA) denote the work done in the 

 sum of all the courses of a given subject; for 

 example, there may be four courses in physics. 

 Let A denote the whole academic work in stu- 



